Speed-retarding device for lifting-jacks



F,'l GORMLEY.

SPEEURETARDING DEVICE FOR UFTING JACKS.

APPLICATION HLED IULY 22,1920.

Patented Nov. 1, 1921.

pa W\\\ F. L. GOHIVILEY.4

SPEED RETARDING DEVICE FOR LIFTING JACKS. APPLICATION HLED JULY 22, |920.

1,395,340. Patented Nov. 1, 1921.

3 SHEETS-SHEET 2. FL3.5. 62

a? Ewen/iur:

i F. L. GORMLEY. SPEED RETARDING DEVICE FOR LIFTING JACKS. APPLICATION FILED JULY 22.1920.

1 ,395,340. Patented Nov. 1, 1921.

3 SHEETS-SHEET 3.

y Ewen/hir: frank .12.Gorm1ey,

FRANK L. GORMLEY, 0F BROOKLINE, MASSACHUSETTS,

ASSIGNOR TO A. O. NORTON,

INC., OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

SPEED-RETARDING- DEVICE FOR LIFTING-JACKS.

i Application filed .Tilly 22,

To all whom t may concern.'

Be it known that I, FRANK L. GonMLiiY, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and Commonwealth of Massachusetts. have invented certain new and useful Improvements in SpeedRetarding Devices for Lifting-Jacks, of which the following is a specification. j

This invention relates to speed retarding devices for lifting jacks and the like and particularly to devices of 4this character which are adapted to be applied to the high speed end ofV a train of gears actuated only during the lowering of the load-supporting member.

The object of the invention is the production of a simple mechanism which may be applied readily to the usual worm shaft of a lifting jack and which will eiiiectually control the speed of the saine, said mechanism being provided with means whereby the speed may be varied as desired.

The invention consists of two dash pots having pistons therein connected to the worm shaft in such a manner that said pistons will always be moving in opposite directions during the operation of the jack, said dash pots and pistons being provided with suitable valves whereby the air in advance of each Apiston has a limited outlet from said dashV pots thereby providingmeans for maintaining the rotation of said worm shaft at a uniform speed.

The invention further4 consists of connecting the air outletsfrom both dash pots with a single discharge pipe having a valve therein which is adapted to regulate the discharge of air from said dash pots and thereby vary the speed of rotation of the pistonactuating member.

The invention further consists in certain novel features ofconstruction and arrangement of parts which will be understood readily by reference to the description of the drawings and to the claims to be hereinafter given. y

For the purpose of illustrating the invention, one preferred form thereof is illustrated viii the drawings, this form having been found to give satisfactory and reliable results although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and the invention is Specification of Letters Patent,

Patented Nev. 1, 1921'. 1920. Serial No. 398,114.

not limited to the precise arrangement and organization of these instrumeiitalities as herein shown and described, except as required by the scope of the appended claims. @f the drawings:

Figure 1 represents a horizontal section of a lifting jack .embodying the features of the present invention, the cutting plane being on line 1, 1, on Fig. 2.

Fig. 2 represents a vertical section of the same on line 2, 2, on Fig. 1.

Fig. 3 represents an elevation of the cover plate with the various actuating devices secured thereto, the in section.

Fig. 4 represents line 4, 4, on Fig. 3.

Fig. 5 represents an elevation of the dash ypot mechanism, partially in section and drawn to an enlarged scale, with the various parts in inoperative position and the controlling valve closed.

Fig. 6 represents a similar view with the a horizontal section on operating shaft being cut controlling valve partially opened and the Y various parts in operative opposition.

Fig. 7 represents an elevation of the manually controlled braking mechanism with a portion thereof broken in section, and

Fig. 8 represents an elevation of the device for controlling the action of the brake mechanism.

Similar characters throughout ings.

In the drawings, 10 represents a suitable base supporting a stationary standard 11 over the outer periphery of which is fitted a movable sleeve 12, to the upper end of which is threaded a cap 13.

In the upper end of the standard 11 is mounted a nut 14 to which is threaded a liftingscrew 15 having splined to its upper reduced end a bevel gear 16 with which meshes a bevel gear17 formed upon or secured to a revoluble Shaft or spindle 18, the outer end of which is provided with a suitable operating mechanism 19 of any well-known construction.

Between the upper face of the bevel gear 1G and the inner face of the cap 13 are two annular plates 20, 21, between which are interposed a plurality of anti-friction meinbers 22.

The movable member 12 is provided on one side with a flanged projection 24 having indicate like parts the several `figures of the drawa removable plate 25 secured thereto by bolts 25X.

i The plate 25 is provided with a bearing 26 for the spindle or shaft 18 and secured to the hub of the gear 17 is a ratchet wheel 27. l

' is secured a ring` 32 between which and said gear the pawls 30 are positioned.

Y From the back of the free end of each pawl 30 extends a lug 33 on which is disposed a helical spring 34 the outer end of which bears against one of the projections 31 and retains said pawls 30 in engagement n vwith said ratchet wheel 27 under normal conditions.

Beneath the gear wheel 29 is a revoluble shaft 35 having ,secured thereto a pinion 36 meshing with said gear 29 and driven thereby when the movable member 12 of the jack is being lowered.

The shaftr35 has also secured thereto a worm wheel V37 which meshes with a worm 38 revoluble in bearings 39 in the bracket 40 secured to the inner face of the removable plate 25 by screws 40X.

To the reduced end 41 of the worm 38 is secured a brake disk 42 with the periphery of which coacts two brake members 43 pivoted at 44 to the bracket 40.

The lower end of each brake member 43 is provided witha recess 45 in which is positioned one end of a helical spring 46 the opposite ends of said springs being disposed in the recesses 47 and 48 in the removable plate 25 and bracket 40. i

Between the lower adjacent ends of the brake members 43 is positioned a fiat sided projection 49 formed upon the actuating lever 50.

A portion of the flat sided projection 49 is cylindrical and positioned in a cylindrical hole in the flange of the removable plate 25.

. The springs 46 normally retain the brake members in contact with the periphery of the disk 42 and prevent its rotation until the actuating` lever 50 is moved to cause said flat sided projection 49 to separate said brake members 43 and remove them from contact with Athe disk 42.

As thus far described the jack is the same as that shown and described in Letters Patent No. 1,324,345 issued to me Dec. 9, 1919. i In the present instance the governor mechanism described in the above-entitled patent is dispensed with and a speed retarding device of an entirely different character is substituted therefor.

This. speed retarding device consists of a disk 51 secured to the reduced end 52 of the worm 38, said disk 51 having a lateral stud 53 extending through a slot in a reciprocating member 54.

Each end of the member 54 is pivotally connected at 55 to a piston 56 adapted to reciprocate in a cup-shaped member or dash pot 57 Each dash pot 57 i's provided with an air passage 58 communicating with the inner end of said dash pot and normally closed by the spring-pressed valve 59.

The opposite ends of the passages 58 communicate with the pipes 60 both connecting with a T 61, one branch of'which has a discharge pipe 62 extending therefrom, the outer end of which is provided with a valve 63 by which the amount of air to be forced from the dash pots 57 may be controlled.

Each piston 56 is provided with one or more spring-pressed valves 64 adapted to be opened on the out-stroke-of the piston to admit air to said dash pots 57.

On the in-stroke of the pistons 56, the valves 64 will be closed and the valves 59 opened thus providing a. means whereby the air in the dashpots 57 may be expelled therefrom.

The amount of air expelled will depend upon the amount of opening of the controlling valve 63.

VThe air expelled from `one dash pot 57 is prevented from entering the other dash pot by means of the valve 59 and therefore ythe only outlet therefor will be through pipe 62 and controlling valve 63.

It will be noted that at all times one piston is moving inward and when the controlling valve 63 has been set for a desired speed, the rotation of the worm 38 will be retarded to conform to this predetermined speed..

As a consequence the rotation of the worm 38 will be at a uniform speed forany one setting of the valve 63, but a variation in speed may be secured by manually actuating the said valve 63 to provide a greater or lesser opening as desired.

The removable cover plate 25 is provided with a support 67 for the dash pots 57 and a semi-cylindrical recess into which portions of the brake mechanism extend. V Y

W'hen the cover plate 25 is removed from the flanged projection' 24 all of the devices during the rotation of the worm gear 37 rotary movement will be imparted to the shaft 71 and the disks 42, 52.

When the brake members 43 are removed from the brake disk 42, the jack is free to lower under its load.

Should the jack under an excessive load start to rotate the worm 38 at too great a speed for safety the speed will be retarded by means of the pistons 56 reciprocating in the dash pots 57 and the worm will be compelled to rotate at its normal predetermined speed.

When pressure is released from the actuating lever 50, the springs 46 will force the brake members 43 into contact with the periphery of the disk 42 and lowering of the jack.

When it is desired to raise the movable member 12, the operating mechanism 19 is manipulated to turn the spindle 18 and gear 17 formed thereon in the direction of the arrow a on Fig. 3 of the drawing.

IVhen this isk done the ratchet 27 will freely pass the pawls 30 without actuating the spur gear 29. v

While lifting the load the operating mechanism will act directly upon the movable member 12 through the gears 17 and 16 and screw 15 without affecting the speed retarding and braking devices.

When the weight has been lifted sufficiently, it will be retained in its elevated p0- sition by means of the friction members 43 coacting with the brake disk 42 and preventing the rotation of the worm 38.

When it is desired to lower the load supported by the movable member 12, the friction members 43 are removed from contact with the disk or wheel 42 by pressing upon the arm 0r lever 50 and with the pawls 30 in engagement with the teeth of the ratchet 27, the gear 29, pinion 36, worm wheel 37 and worm 38 will be driven by the rotation of the gear 17 and its spindle 18.

The pitch of the wormthread is such as to permit the jack to start automatically to descend under its own load when its brake is released.

Should an excessive load be upon the cap 13 so that member -12 starts to move downwardly too rapidly, its movement will be arrested by the action of the speed retarding device.

If it is desired to entirely stop the lowering of the load, pressure is removed from the actuating lever 50 and the brake members 43 will be forced into contact with the disk 42.

rIhe multiplication of the braking power through the high ratio gearing and through the worm and worm wheel will serve to make possible the quick and easy stoppage by a light pressure of the brake, of the descending jack at any point.

prevent further It is believed that the operation and many advantages of the invention will be readily understood without further description.

Having thus described my invention, I claim:

1. In a combinationwith a lifting jack adapted to lower under the weight ofthe load and including a load-supporting member, a shaft adapted to Vbe rotated in one direction only, and mechanism between said load-supporting member and said shaft for imparting rotary movement to said shaft during the lowering operation at a speed greater than that of said load-supporting member; a member secured to and revoluble with said shaft; a dash potg-and a piston therein adapted to be recipro'cated by said revoluble member.

2. In a combination with a lifting jack adapted to lower under the weight of the load and including a load-supporting member, a shaft adapted to be rotated in one direction only, and mechanism between said load-supporting member and said shaft for imparting rotary movement to said shaft during the loweringoperation at a speed greater than that of said load-supporting member; a member secured to and revoluble with said shaft; a` dash pot having an air outlet at its inner end; a piston therein adapted to be reciprocated by said revoluble member; and means for controlling the discharge of air through said outlet.

3. In a combination with a` lifting jack adapted to lower Vunder the weight'of lthe load and including a load-supporting inember, a shaft adapted to be rotated in one direction only, and mechanism between said load-supporting member and said shaft for imparting rotary movement to said shaft during the lowering operation at a speed greater than that of said load-supporting member; a member secured to and revoluble with said shaft; a dash pot; a piston therein adapted to be reciprocated by said revoluble member; a valve in said piston adapted to close on the in-stroke of the piston and open on the out-stroke thereof; and means for controlling the discharge of air through said outlet.

4. In a combination with a lifting jack adapted to lower under the weight of the loadand including a load-supporting member, a shaft adapted to be rotated in one direction only, and mechanism between said load-supporting member and said shaft for imparting rotary movement to said shaft during the lowering operation at a speed greater than that of said load-supporting member; a member secured to and revoluble with said shaft; two dash pots having air outlets at their inner ends; pistons in said dash pots; mechanism between said revoluble member and said dash pots for simultaneously moving one piston inwardly and the other outwardly; and means for controlling the discharge of air through each `outlet during the instroke of each piston.

5. In a combination with a lifting jack adapted to lower under the weight of the load and including a load-supporting member, a shaft adapted to be rotated in one direction only; and mechanism between said load-supporting member and said shaft for imparting rotary movement to said shaft during the lowering operation at a speed greaterv thanV that of said load-supporting member; a member secured to and revoluble with said shaft; two dash pots having air outlets at their inner ends; pistons in said dash pots; mechanism between said revoluble member and said dash pots for simultaneously moving one piston inwardly and the other outwardly; and a valve common to both dash pots for controlling the discharge of air through each outlet during the in-stroke of each piston.

`6. A speed retarding device for load-lifting apparatus consisting of a load-supporting member and a revoluble shaft positively driven in one direction only by the lowering of said load-supporting member; a member secured to and rotatable with said shaft; two dash pots having air outlets at their inner ends; pistons in said dash pots; mechanism between said revoluble member and said pistons for simultaneously moving one piston inwardly and the other outwardly; and means air vthrough each outlet during the instroke of each piston.

7. A speed retarding device for load-lifting apparatus consisting of a load-supporting memberand a revoluble shaft positively driven in one direction only by the lowering of said load-supporting member; a member secured to and rotatable with said shaft; two dash pots having air outlets at their inner ends; pistons in said dash pots; mechanism between said revoluble member and said pistons for simultaneously moving one piston inwardly and the other outwardly; and a valve common to both dash pots for controlling the discharge of air through each outlet during the iii-stroke of each piston.

8. A speed retarding device for load-lifting apparatus consisting of a load-supportfor controlling the discharge of v ving member and a revoluble shaft positively valves in said outlets adapted to be closed during the outstrolre of the pistons and opened during the in-stroke thereof; and means for controlling the discharge of air through each outlet.

9. A speed retarding Vdevice for load-lifting apparatus consisting of a load-supporting member and a revoluble shaft positively driven in one direction only by the lowering of said load-supporting member; a member secured to and rotatable with said shaft; two dash pots having their outlets at their inner ends; pistons in said dash pots; mechanism between said revoluble vmember and said pistons for simultaneously moving one piston inwardly and the other outwardly; valves in said outlets adapted to be closed during the out-stroke of the pistonsl and opened during the in-stroke thereof; valves in said pistons adapted to be closed during the iii-stroke of said pistons and opened during the out-stroke thereof; and means for controlling the discharge of air through each outlet.

l0. A speed retarding device for load-lifting apparatus consisting of a revoluble member; two dash pots having air outlets at Vtheir inner ends; pistons in said dash pots; a bar connecting said pistons having an elongated transverse slotI therein; a stud on said revoluble member extending through said slot and adapted to impart reciprocatory movementv to said bar and pistons; valves in said outlets adapted to be closed during the out-stroke of the pistons and opened during the iii-stroke thereof; and means for controlling the discharge of air through each outlet.

f Signed by me at 746-7 Old South Bldg., Boston, Mass., this 17 th da of July, 1920. FRANK GORMLEY.

Witnesses:

VALTER E. LOMBARD, NATHAN C. LOMBARD. 

